If you appreciated the first use of push-to-pass during qualifying for an NTT IndyCar Series event at The Thermal Club, expect something similar in a few months.
To add a new layer of entertainment to qualifying or heat races at Thermal’s $1 Million Challenge, IndyCar enabled the push-to-pass (P2P) system on each car, giving drivers 40 seconds of extra power — approximately 50 horsepower from an increase in turbocharger boost and RPM — to use while attempting to set their fastest laps.
“I thought the 40 seconds they gave you for qualifying was good because it added this pressure factor,” Pietro Fittipaldi of Rahal Letterman Lanigan Racing told RACER. “You can use 40 seconds in one lap and gain six to seven tenths (of an improvement), but you must ensure that you do not encounter traffic during that lap. So there’s the added pressure of feeling like it’s a one-lap qualifying session. I thought it was cool. I enjoy that sort of sensation upon qualifying.”
Fittipaldi also like the strategy components and risk that having a limited number of P2P brought to qualifying.
“Definitely, with this type of boost available, I’d say qualifying could be slightly shorter,” he added. “Because the one thing you need to keep in mind as you go through qualifying is that you have a set of Firestone [primaries] and a set of [faster alternates], and if you only have 40 seconds or whatever, you’re obviously going to save those seconds for the [alternates] because you’re so much faster on that one lap.
“Unfortunately, when I performed my qualifying, I utilized all of my 40 seconds and ended up catching traffic, and then the red flag came out, so when I set my fastest lap, I had no push-to-pass remaining. Fortunately, I was able to qualify sixth, but it might have ended much better for me, so you must plan when you go, and you may make a mistake on that lap or encounter traffic. “I think it might shake things up.”
P2P was allowed in qualifying, breaking with convention, as it had previously only been used on race days at road and street circuits. Beyond its new addition to qualifying at Thermal, RACER has learned that the decision to activate P2P in qualifying was part of the series’ larger fact-finding effort.
Although Thermal will be a one-time exception with turbo-based P2P in qualifying, IndyCar is using the results from the session at the Southern California circuit to prepare for the transition to hybridized powertrains this summer, when added horsepower will become a standard feature in qualifying.
Once the energy recovery systems (ERS) developed in collaboration with Chevrolet and Honda are operational, drivers will be able to use 60hp hits in qualifying via the motor generator units and energy storage systems contained in the bellhousings. IndyCar will allow its teams to employ both P2P and the ERS boost in races, but only the 60 horsepower ERS punch will be allowed in qualifying.
With hybrid testing ongoing ahead of their scheduled debut in July, guidelines for all aspects of how the ERS units will be utilized in competition have yet to be drafted. It is currently unknown whether the ERS boost will be engaged in all qualifying sessions, including ovals, or only on road and street circuits. Another point of interest is if the series would limit the amount of ERS boost that can be deployed per lap.
The last hybrid test on the Indianapolis Motor Speedway road course demonstrated that harvesting and delivering ERS energy may occur two to three times per lap, which is more than the series had anticipated.
The choice of ESS device determines the fast-charging capability. Honda, which designed and manufactured the ESS, chose a quick-charging/low-voltage supercapacitor technology that, unlike more traditional battery-based systems, is lighter, stores less energy, and can deploy and regenerate energy quickly.
Cars in various hybrid racing series must harvest numerous times per lap to recharge their batteries, whereas IndyCar’s supercapacitor-based technology can fill and deploy multiple times per lap. The series is considering limiting the amount of ERS power that can be used per lap.
If the per-lap limit is used, it will be a departure from how the series manages P2P, which now allocates a set amount of P2P deployment time for each road and street circuit race. In the new world of hybridization, drivers would continue to have 150 seconds of P2P, for example, to conserve and use strategically throughout a race, and once those 150 seconds are up, the technology is turned off.
However, with IndyCar’s approach to ERS, there would be no time constraints; the 60hp increase would be available throughout the race. There could be a limit on how much ERS power can be liberated per lap, which would align with the P2P philosophy in which the times, locations, and durations of ERS power capturing and releasing would require some strategic planning.
That sounds complicated—at least more complicated than the simple P2P system—and it is.
“When we tested the hybrid last week, that was how it was set up,” Fittipaldi remarked in an interview. “Essentially, every lap allowed you to use 350 kilojoules of power. When you move from 100 percent SOC (state of charge) to zero, you only utilize around 150 kilojoules. So, basically twice in a lap, and possibly again for a portion of a third, you must charge in order to run again and deploy the allotted number of kilojoules per lap.
“So, what changes is your power-generation plan. You can regenerate during braking or during coasting phases, and this is where the tactics and game alter because everyone will be able to employ the 350 kilojoules. The difference will be how you renew that power across the lap, because differing techniques affect both the car’s balance and fuel efficiency.”
ERS power in qualifying and races, but with per-lap limits on both and across all tracks? Plus P2P in races, but just on the roads and streets? While establishing the rules for the next hybrid competition, IndyCar will have access to a variety of exciting new choices.
“That’s where the game gets fascinating because everyone will be able to deploy the same thing, but how will it be regenerated? And what’s the most efficient method? And what improves your balance the most?” Fittipaldi explained. “There’s a lot going on already, and this takes it to another level.”
